A patent filed by Apple shows a pair of headphones that flip open to turn into neck-worn speakers.

The AirPods aren't the only bit of audio witchcraft Apple has been working on - the firm has patented a pair of headphones that turn into speakers.

The headphones contain sensors that would transform them into a set of speakers when positioned correctly, according to Patently Apple.

These 'Dual Use' headphones would sense when they're being worn on the ears, and when they're loose around the neck, pointing upwards. In the latter mode, the built-in amplifiers would increase the sound, effectively turning them into wearable speakers.

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But the idea isn't limited to over-ear models. The patent also covers in-ear and clip-on headphones with the same functionality. These would appear to have a button to switch between modes.

The technology isn't that far off either. The iPhone 7 is already capable of switching from stereo sound when in landscape mode, and cutting out the sound from the ear speaker to work in mono when turned portrait - this is to ensure it doesn't deafen the user if they receive a call. It's likely the patented pair would work in a similar fashion.

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